2.17 Metallic bonding
In covalent bonding, pairs of atoms share electrons. In a third kind of bonding, metallic bonding, many atoms share the same electrons. Individual atoms give up their valence electrons and the delocalized electrons are free to move and interact with all the positively charged ions in the structure (Figure 2.17). Metallic bonding, is especially common in minerals involving transition metals. Gold, silver, and copper are examples of minerals with metallic bonds. Because valence electrons move easily throughout the structure, metallically bonded compounds are good conductors of heat and electricity. Electrons are easily transferred along wires, for example. Minerals with metallic bonds may be malleable and have only low-to-moderate hardness, reflecting the loose nature of their metallic bonds.